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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36146 results found.

  1. GRB 190519A: Enhanced Swift-XRT position
  2. GRB 190519A: Fermi GBM observation
  3. GRB 190519A: Swift detection of a burst
  4. GRB 190519A: Fermi GBM Final Real-time Localization
  5. LIGO/Virgo S190517h: INTEGRAL prompt observation
  6. GRB 190511A: Swift/UVOT further analysis
  7. Fermi Trigger 579814215 / GRB 190517813 / GRB190517A: BALROG localization
  8. GRB 190517A: Fermi GBM Final Real-time Localization
  9. LIGO/Virgo S190517h: Swift/BAT Counterpart Search
  10. LIGO/Virgo S190517h: Insight-HXMT/HE observations
  11. LIGO/Virgo S190517h: Fermi GBM Observations
  12. GRB 190515A: CALET Gamma-Ray Burst Monitor detection
  13. LIGO/Virgo S190517h: INTEGRAL/SPI-ACS prompt observation
  14. GRB 190515B: Swift/UVOT Upper Limits
  15. GRB 190515B: BOOTES-4/MET and 2.2m CAHA optical limits
  16. GRB 190515B: Swift-BAT refined analysis
  17. GRB 190515A: Insight-HXMT/HE detection
  18. GRB 190515A: Fermi GBM detection
  19. GRB 190515B: Swift-XRT refined Analysis
  20. GRB 190515A: Fermi-LAT detection
  21. GRB 190515B: Optical observations from OSN
  22. GRB 190515B: Enhanced Swift-XRT position
  23. GRB 190515B: Kitab Observatory optical upper limit
  24. Correction to GRB name for Swift trigger 903845
  25. GRB 190515B: Prompt enhanced Swift-XRT position
  26. GRB 190515B: Swift detection of a burst
  27. GRB 190510A: CALET Gamma-Ray Burst Monitor detection
  28. GRB 190515A: Fermi GBM Final Real-time Localization
  29. LIGO/Virgo S190513bm: Swift/BAT Counterpart Search
  30. LIGO/Virgo S190513bm: Insight-HXMT/HE observation
  31. GRB 190510B: AstroSat CZTI detection
  32. LIGO/Virgo S190513bm: Fermi GBM Observations
  33. GRB 180416D: AstroSat CZTI detection
  34. Konus-Wind observation of GRB 190511A
  35. Konus-Wind observation of GRB 190510A
  36. LIGO/Virgo S190513bm: INTEGRAL prompt observation
  37. LIGO/Virgo S190512at: Insight-HXMT/HE observation
  38. GRB 190512A: Swift-BAT refined analysis
  39. LIGO/Virgo S190512at: Swift/BAT Counterpart Search
  40. LIGO/Virgo S190512at: Fermi GBM Observations
  41. GRB 190512A: Fermi GBM observation
  42. GRB 190511A: Swift-BAT refined analysis
  43. GRB 190512A: Swift detection of a burst
  44. GRB 190512A: Fermi GBM Final Real-time Localization
  45. GRB 190511A: Swift-XRT refined Analysis
  46. IPN triangulation of GRB 190510A (short)
  47. GRB 190511A: Swift/UVOT Detection
  48. GRB 190511A: NOT optical afterglow
  49. GRB 190511A: Fermi-LAT detection
  50. GRB 190511A: Fermi GBM observation
  51. GRB 190511A: Enhanced Swift-XRT position
  52. GRB 190511A: Swift detection of a burst
  53. GRB 190511A: Fermi GBM Final Real-time Localization
  54. LIGO/Virgo S190510g: Insight-HXMT/HE updated observation
  55. LIGO/Virgo S190510g: Swift/BAT Counterpart Search
  56. Konus-Wind observation of GRB 190501A
  57. LIGO/Virgo S190510g: Insight-HXMT/HE observation
  58. GRB 190510A: Fermi GBM Final Real-time Localization
  59. GRB 190508A: GOTO optical search - no counterparts
  60. GRB 190508B: Fermi GBM Final Real-time Localization
  61. GRB 190508A: Fermi GBM Final Real-time Localization
  62. GRB 190507B: GOTO optical counterpart search
  63. GRB 190507B: Fermi GBM Final Real-time Localization
  64. GRB 190501A: Swift XRT and UVOT Observations
  65. LIGO/Virgo S190426c: Konus-Wind observations
  66. LIGO/Virgo S190425z: Konus-Wind observations
  67. IceCube-190504A: MASTER optical monitoring analysis
  68. Fermi Trigger 578903308 / GRB 190507270 / GRB190507A: BALROG localization
  69. GRB 190507A: Fermi GBM Final Real-time Localization
  70. Update to the Fermi GBM GCN Reporting
  71. IceCube-190504A: Insight-HXMT/HE observation
  72. GRB 190501A: CALET Gamma-Ray Burst Monitor detection
  73. IceCube-190503A: Insight-HXMT/HE observation
  74. IPN triangulation of GRB 190504A (short)
  75. LIGO/Virgo S190503bf: Swift/BAT Counterpart Search
  76. IceCube-190503A: Insight-HXMT/HE observation
  77. LIGO/Virgo S190503bf: Fermi-GBM Observations
  78. IceCube-190503A: INTEGRAL prompt observation
  79. LIGO/Virgo S190503bf: INTEGRAL prompt observation
  80. Correction in name: GRB 190501B (not GRB 190501BA) : AstroSat CZTI detection
  81. GRB 190501B: AstroSat CZTI detection
  82. IPN Triangulation of GRB 190501A (long/bright)
  83. GRB 190501A: Swift ToO observations
  84. GRB 190501A: GOTO optical counterpart search
  85. Fermi Trigger 578462495 / GRB 190502168 / GRB190502A: BALROG localization
  86. GRB 190501A: refined position from AGILE/GRID analysis
  87. GRB 190501A: AGILE/GRID detection
  88. GRB 190501A: AGILE/MCAL and scientific ratemeters detection of a burst
  89. GRB 190429A: AstroSat CZTI detection
  90. GRB 190427A: CALET Gamma-Ray Burst Monitor detection
  91. LIGO/Virgo S190425z: RATIR non-detection of the Swift/UVOT source
  92. GRB 190427A: Swift/UVOT Upper Limits
  93. Fermi Trigger 578170097 / GRB 190428783 / GRB190428A: BALROG localization
  94. GRB 190427A, Swift-BAT refined analysis
  95. If you have problems wrt GCN ( GRB, LIGO/Virgo, etc) and need to send email to the operator
  96. GRB 190419A: AstroSat CZTI detection
  97. GRB 190427A: Fermi GBM detection
  98. GRB 190427A: Lick/Nickel telescope optical observations
  99. GRB 190427A: MITSuME Akeno optical upper limits
  100. GRB 190427A: COATLI Optical Observations

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